Achoo: Understanding 5 common allergens - How airborne particles cause allergic reactions

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Sniffling, sneezing, stuffed-up nose, itchy watery eyes; for allergy sufferers, these symptoms can be a part of daily life. When the seasons change, a flood of airborne contaminants is released. During the spring, budding plants, trees, and grass spreads allergens that can make it hard to breathe. In the fall and winter, when windows and doors are kept closed, many contaminants can get trapped in your home. And year-round, dust mite debris, mold spores, and tobacco smoke linger in the air and around the house, triggering allergic responses.

Allergic reactions explained

What's happening in your body when you have an allergic reaction? During allergy season, when people joke that their body is at war, they aren't that far from the truth. When you're allergic to a particular thing, pollen for example, your immune system sees pollen as an invader and responds by producing immunoglobulin E (IgE) antibodies, and then attacks the pollen with them. The antibodies cause chemicals to be released that trigger allergy symptoms. According to the American Academy of Allergy Asthma and Immunology, each type of IgE has a specific radar for each type of allergen. That's why some people are only allergic to cat dander (they only have the IgE antibodies specific to cat dander); while others have allergic reactions to multiple allergens because they have many more types of IgE antibodies.

Common allergy symptoms:

  • Sneezing
  • Runny nose
  • Stuffy nose
  • Itchy nose, mouth or throat
  • Postnasal drip
  • Scratchy throat
  • Cough
  • Chest tightness
  • Wheezing
  • Itchy, red or watery eyes
  • Eczema
  • Rashes
  • Hives
  • Fatigue
  • Irritability


Dander and pet allergens

Pet allergies are often blamed on a cat or dog hair, when in fact; pet hair is not an allergen. The proteins found in dander and saliva are the actual culprits. These proteins are released in saliva and from skin glands, so when skin and fur are licked, it's getting a second dose of the protein, which dries and then is shed off in the form of dander.

Dust mites

Tiny eight-legged relatives of the spider and tick, dust mites have no eyes or respiratory system. Too tiny to see with the naked eye, a mite is less than half a millimeter ranging from one quarter to one-third of a millimeter in size.

Mold and mold spores

Molds are microscopic organisms that belong to the fungi kingdom, so they are neither plant nor animal. When mold reproduces; its seed-like spores are a mere 3 to 40 microns in size invisible to the naked eye. Molds keep the natural world livable by decomposing leaves, wood, and other plant debris. It's unknown just how many types of mold exist, but estimates range from 10,000 to 300,000 or more. Found both indoors and out, mold is happiest in warm, damp, and humid conditions, and while mold spores can survive harsh, dry conditions, it limits their reproduction and normal growth.


Pollen is made of very tiny grains and it usually looks like fine yellow dust. That's how it got its name; in Latin, pollen means fine powder. The fertilizing element of a flowering or conifer plant, pollen carries the cells that enable a plant to reproduce. Called pollination, it's responsible for the growth of apples, oranges and other fruits without pollination, trees couldn't grow fruit.


The dictionary describes smoke as, visible suspension of carbon or other particles in air, typically one emitted from a burning substance. In addition to several known carcinogens, smoke contains fine particles composed of wood tars, gases, soot, and ashes. Things like cigarettes, cigars, wood-burning stoves, fireplaces, and even the kitchen stove can emit these particles of carbon into the air, and affect the quality of the air we breathe.